Reactive flame retardants for polyurethane and polyisocyanurate foams

ABSTRACT

The present invention provides novel cyclic phosphorus-containing compounds, namely hydroxyl-functional phospholene-1-oxides, serving as highly efficient reactive flame retardants in urethane systems, particularly in flexible polyurethane foams, rigid polyurethane foams and rigid polyisocyanurate foams. The invention further provides fire-retarded polyurethane compositions comprising said hydroxyl-functional phospholene-1-oxides.

This application claims priority to International Application No.PCT/US2016/061248 filed Nov. 10, 2016; which claims priority of U.S.Provisional Patent Application No. 62/254,848 filed Nov. 13, 2015, theentire contents of which are incorporated herein by reference in theirentirety.

FIELD OF THE INVENTION

The disclosure herein provides for novel cyclic phosphorus-containingcompounds, namely hydroxyl-functional phospholene-1-oxides, serving ashighly efficient reactive flame retardants in urethane systems,particularly in flexible polyurethane foams, rigid polyurethane foamsand rigid polyisocyanurate foams. The invention further providesfire-retarded polyurethane compositions comprising saidhydroxyl-functional phospholene-1-oxides. The expressions “fireretardants” and “flame retardants” are used herein interchangeably.

BACKGROUND OF THE INVENTION

Brominated or phosphorus-based flame retardants are known to be highlyeffective and in many cases are the only options for reducing the firerisk of synthetic materials such as rigid or flexible polyurethanefoams. However, the growing public and governmental scrutiny ofchemicals, and in particular flame retardants, has increased over theyears. The goal is towards more sustainable, reactive, polymeric and/orhalogen-free new products. Scrutiny greatly diminishes if a flameretardant is reacted into the polymer matrix and cannot be leached-out.

Thus, there is a demand for reactive phosphorus-containing fireretardants for flexible polyurethane, rigid polyurethane andpolyisocyanurate foams, possessing such features as high phosphoruscontent, clear light color and good compatibility with polyether polyolsand polyester polyols employed in the polyurethane industry.

SUMMARY OF THE INVENTION

The present invention provides novel reactive phosphorus-containinghydroxyl-functional compounds possessing highly satisfactoryflame-retarding characteristics and having good compatibility with thepolyol components of a polyurethane system. The novelphosphorus-containing hydroxyl-functional compounds are fully reactivethrough their hydroxyl-functional group. This means that the flameretardants of the invention become integrated into the polymersubstrate, for example a rigid or flexible foam, such that they are notreleased into the environment and are not likely to penetrate throughcell membranes of living tissue, and therefore do not pose a healthhazard. The invention further provides polyurethane compositions,including but not limited to polyurethanes and polyisocyanuratecompositions containing the said novel reactive phosphorus-containinghydroxyl-functional compounds that exhibit excellent fire retardancy.

The term “foam” as used herein refers to polyurethane foams, which inturn can comprise, any one or more of flexible, semi-rigid, and rigidpolyurethane foams or polyisocyanurate foams. The term “polyurethane” asdescribed herein can encompass both polyurethane materials andpolyisocyanurate materials. The polyurethane and/or polyisocyanuratedescribed herein, or claimed herein, as comprising, consistingessentially of or consisting of the hydroxyl-functionalphospholene-1-oxide compounds of the general formula (I-A) and (I-B),and the group of novel phosphorus-containing polyol reaction products ofthe partial phosphorylation of polyalcohols, which contains at least onephosphorus-containing group of the general formula (I-B), are allunderstood herein to contain the aforementioned formula(e) as reactivematerials, i.e., the aforementioned formula(e) are reacted into thepolyurethane and/or polyisocyanurate material's structure, in which casethe aforementioned formula(e) may not be present, or would not bepresent in the same structural formula(e) as described herein, but wouldbe present in the polyurethane and/or polyisocyanurate material as areaction product of a polyol, a polyisocyanate and the structuralformula(e) described herein.

The present invention provides novel hydroxyl-functionalphospholene-1-oxide compounds of the general formula (I-A) and (I-B),and a group of novel phosphorus-containing polyol reaction products ofthe partial phosphorylation of polyalcohols, which contains at least onephosphorus-containing group of the general formula (I-B), whereinformula (I-A) is:

wherein:

the dashed line indicates a double bond located between the carbon atomat position 3 and one of the carbon atoms at positions 2 and 4 providedthat each of the two ring carbon atoms which are not part of the doublebond are each bonded to one of the two hydrogen atoms shown in thestructural formula (I-A),

R¹, R², R³ and R⁴ are independently selected from H, a linear orbranched alkyl group containing from 1 to 4 carbon atoms, preferablymethyl or ethyl; or chlorine,

and X is either

(Z)_(k)—R⁷ or

and when X is Z is

((Z)_(k)—R⁷, Z is —(Y—O)_(n)—, wherein Y is a linear or branchedalkylene group containing from 2 to 8 carbon atoms, preferably from 2 to4 carbon atoms, more preferably ethylene, propylene, or isopropylene,and n represents an integer from 1 to 20, preferably from 1 to 5,

k may be 0 or 1;

R⁷ is selected from hydrogen, a hydroxy-terminated linear or branchedalkylene group containing from 2 to about 8 carbon atoms, preferablyfrom 2 to 4 carbon atoms; and,

provided that when k is zero, R⁷ is the hydroxy-terminated linear orbranched alkylene group and when k is 1, R⁷ is hydrogen, and

when X is

R⁵ and R⁶ are each independently selected from H, a linear or branchedalkyl group containing from 1 to 8 carbon atoms, preferably from 1 toabout 4 carbon atoms and most preferably any one of methyl, ethyl orpropyl, a linear or branched alkenyl group containing from 2 to 8 carbonatoms, preferably from 2 to about 4 carbon atoms, a hydroxyalkyl groupcontaining from 2 to 4 carbon atoms, a halo-substituted alkyl groupcontaining from 1 to 8 carbon atoms, an alkoxy group containing from 1to 8 carbon atoms, preferably from 1 to about 4 carbon atoms, an arylgroup containing from 6 to 12 carbon atoms, preferably from 6 to about 8carbon atoms, and an alkylaryl group containing from 7 to 16 carbonatoms, preferably from 7 to about 12 carbon atoms, or R⁵ and R⁶ arebonded to each other to form a cycloalkyl group containing from 5 toabout 8 carbon atoms, preferably 6 carbon atoms; and wherein formula(I-B) is:

wherein:

the dashed line indicates a double bond located between the carbon atomat position 3 and one of the carbon atoms at positions 2 and 4, providedthat each of the two ring carbon atoms which are not part of the doublebond are each bonded to one of the two hydrogen atoms shown in thestructural formula (I-B);

R¹, R², R³ and R⁴ are independently selected from H, a linear orbranched alkyl group containing from 1 to 4 carbon atoms, preferablymethyl or ethyl; or chlorine,

each of n¹ and n² is an integer equal to or greater than 1, preferablyeach of n¹ and n² is from about 1 to about 5, with n¹+n² being equal toor greater than 3, preferably from about 3 to about 5 and

Z² is a moiety derived from a branched polyol which has a valence ofn¹+n², and is of the general formula:

wherein R is selected from the group consisting of:

and where each R⁸ is H or is an alkyl of from 1 to 4 carbon atoms, x is≥1, preferably from 1 to about 4, y is 2 or 3; z is an integer of from 2to 5; and, m≥1, preferably m is 1.

There is also provided herein a process for the preparation of saidnovel compounds.

The novel compounds of formula (I-A) can be prepared by the reaction of1-hydroxy-phospholene-1-oxides of formula (II) with compounds having anoxirane group, wherein formula (II) is:

wherein R¹, R², R³ and R⁴ are as defined, and the dashed line indicatesa double bond located between the carbon atom at position 3 and one ofthe carbon atoms at positions 2 and 4, provided that each of the tworing carbon atoms which are not part of the double bond are each bondedto one of the two hydrogen atoms shown in the structural formula (II),

The novel compounds of formula (I-A) can also be prepared by thereaction of 1-halo-phospholene-1-oxides of formula (III) with aliphaticdiols, wherein formula (III) is:

wherein R¹, R², R³ and R⁴ are as defined and the dashed line indicates adouble bond located between the carbon atom at position 3 and one of thecarbon atoms at positions 2 and 4, provided that each of the two ringcarbon atoms which are not part of the double bond are each bonded toone of the two hydrogen atoms shown in the structural formula (III), andA is chlorine or bromine,

The novel phosphorus-containing polyols of the invention, for examplethose of Formula I-B, can be prepared by the reaction of1-halo-phospholene-1-oxides of formula (III) with aliphatic polyols.

The reactive substituted hydroxyl-functional phospholene-1-oxides ofthis invention possess high phosphorus content, have good hydrolytic andthermal stability, exhibit good compatibility with the polyol componentsof the polyurethane system, and are useful as highly efficient reactiveflame retardants in flexible and rigid polyurethane and polyisocyanuratefoams.

The present invention further provides fire-retarded polyurethanecompositions comprising said novel phosphorus-containinghydroxyl-functional compounds which can be used either individually orin an admixture with one another or with other flame retardants,including bromine-containing flame retardants and phosphorus-containingflame retardants.

All the above and other characteristics and advantages of the inventionwill be better understood through the following illustrative andnon-limitative detailed description of the preferred embodimentsthereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 contains two graphs illustrating the indicative scorchperformance of Preparation Example 1 in comparison to the knowncommercial product Fyrol FR-2 and foam made without an FR additive intwo polyether foam densities

FIG. 2 is a graph illustrating the indicative scorch performance ofPreparation Example 1 in comparison to the known commercial productFyrol FR-2 and foam made without an FR additive in polyester foam

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In one embodiment the hydroxyl-functional phospholene-1-oxides offormula I-A can be those of the more specific formulae I-A-1 or I-A-2,wherein formula I-A-1 is:

wherein R¹-R⁴, Z, k, R⁷ and the dashed line are as defined above; and,wherein formula I-A-2 is:

and wherein R¹-R⁶ and the dashed line are as defined above.

The hydroxyl-functional phospholene-1-oxides of formula (I-A) of thepresent invention are prepared by the reaction of1-hydroxy-phospholene-1-oxides of formula (II) with compounds of formula(IV), having oxirane groups, which formula (IV) is

wherein:R⁵ and R⁶ are as defined above.

The hydroxyl-functional phospholene-1-oxides of formula (I-A) of thepresent invention are prepared by the reaction of1-halo-phospholene-1-oxides of formula (III) with aliphatic diols offormula (V):

HO—(Z)_(K)—R⁷  (V)

wherein Z, R⁷ and the subscript k are as defined above.

The phosphorus-containing polyols of the present invention, for examplethose of formula I-B, are prepared by the reaction of1-halo-phospholene-1-oxides of formula (III) with aliphatic polyols.

The non-substituted and substituted 1-hydroxy-phospholene-1-oxides (II)and 1-chloro-phospholene-1-oxides (III) employed as starting materialsin the process of the present invention are for the most part well knownin the art. The compounds of formula (II) can be obtained for example byhydrolysis of the corresponding 1-halo-phospholene-1-oxides (III). Thelatter can be prepared for example by the method described in CA2040603, the contents of which are incorporated by reference herein.

Specific oxirane compounds used in the process for preparing thecompounds of formula (I-A) or more specifically (I-A-1) or (I-A-2) ofthe present invention are selected from the group consisting of, but notlimited to, for example, ethylene oxide, propylene oxide,1,2-epoxybutane, 1,2-epoxypentane, 1,2-epoxyhexane, 1,2-epoxy-5-hexene,1,2-epoxy-2-methylpropane, 1,2-epoxyoctane, glycidyl methyl ether,glycidyl isopropyl ether, glycidyl isobutyl ether, glycidyl heptylether, glycidyl 2-ethylhexyl ether, glycidyl allyl ether,trimethylolpropane triglycidyl ether, styrene oxide, cyclohexene oxide,epichlorohydrin and combinations thereof. More preferably, ethyleneoxide, propylene oxide and 1,2-epoxybutane are used as the oxiranecompound.

Specific aliphatic diols used in the process for preparing the compoundsof formula (I-A) or more specifically (I-A-1) or (I-A-2) of the presentinvention are selected from the group consisting of, but not limited to,for example, ethylene glycol, diethylene glycol, triethylene glycol,propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 1,4-butane diol, 2-butene-1,4-diol, 1,5-pentane diol, 1,6-hexanediol, 1,8-octane diol, and other diols having molecular weights up to700.

The aliphatic polyols used in the process for preparing thephosphorus-containing polyols of the invention can generally be anysuitable polyols having at least three reactive hydrogen atoms, examplesbeing those having functionality of from 3 to 6, preferably 3 and 4, andpreferably a molecular weight of from about 100 to about 700. Specificaliphatic polyols can be selected from the group of non-polymericpolyalcohols, for example, trimethylol propane, trimethylol ethane orglycerol.

Preferably, the polyols to be used according to the present inventionare polyether polyols. This class of polyols is obtained by thering-opening addition reaction of one or more alkylene oxides (e.g.,ethylene oxide and propylene oxide) with a suitable reactant containingactive hydrogen atoms, such as alcohols, amine and acids; morespecifically, said reactant may be selected from a group consisting oftriols, novolac resins, pentaerythritol, sorbitol, sucrose,diethylenetriamine and the like. Polyester-polyols may also be usedaccording to the present invention; this class of polyols is obtained bythe condensation reaction of dicarboxylic (or polycarboxylic) acid, suchas adipic acid, phthalic acid or the like, with triols. The aliphaticpolyols used in the process for preparing the phosphorus-containingpolyols of the present invention are selected from polymeric polyolssuch as polyether polyols, polyester polyols, and mixtures thereof.

In a preferred embodiment of the present invention, the reaction of1-hydroxy-phospholene-1-oxides (II) with an oxirane compound is carriedout in a medium of excess oxiranes, with or without an organic solventsuch as isopropanol, 1,4-dioxane, or toluene.

The amount of oxirane compound used in the reaction with1-hydroxy-phospholene-1-oxides (II) is a 5-300% molar excess relative tothe 1-hydroxy-phospholene-1-oxide, and preferably a 50-100% molarexcess. Using a molar excess of the oxirane compound greater than 100%relative to the 1-hydroxy-phospholene-1-oxide is inexpedient due to theneed to recycle a large quantity of oxirane.

The hydroxyl-functional phospholene-1-oxides of formula (I-A) or morespecifically (I-A-1) or (I-A-2) of the present invention have aphosphorus content of about 8-18% by weight and a hydroxyl number ofabout 150-315 mg KOH/g, depending on the 1-hydroxy-phospholene-1-oxideand the oxirane taken for the reaction.

It is preferred, for the preparation of the target hydroxyl-functionalphospholene-1-oxides (I-A) or more specifically (I-A-1) or (I-A-2) withthe highest possible phosphorus content, to react non-substituted ormethyl-substituted 1-hydroxy-phospholene-1-oxides having the highestphosphorus content amongst the 1-hydroxy-phospholene-1-oxides (II), withethylene oxide and propylene oxide.

Thus, the compounds of formula (I-A) or more specifically (I-A-1) or(I-A-2), having particularly valuable properties are those wherein R¹,R³ and R⁴ are each hydrogen, R² is H or methyl, R⁵ and R⁶ are eachindependently selected from H, or R⁵ and R⁶ and methyl, providing thatwhen R⁵ is methyl, R⁶ is hydrogen, and when R⁶ is methyl, R⁵ ishydrogen.

Said reactions are carried out at a temperature of between 40° C. and120° C., and preferably between 70° C. and 90° C. At a temperature lowerthan 40° C. the reaction becomes unacceptably slow. On the other hand,applying a temperature higher than 120° C. is not advisable since atsuch temperatures undesirable decomposition products may be formed.

In a preferred embodiment, the reaction of 1-halo-phospholene-1-oxides(III) with an aliphatic diol is carried out in a medium of excess diol.

The amount of diol compound used in the reaction with1-halo-phospholene-1-oxides (III) is generally a 2 to 10 moles per 1mole 1-halo-phospholene-1-oxide, and preferably a 4 to 8 moles molarexcess. The relatively large excessive amounts of these diols arerequired for minimizing the formation of undesirable di-phospholenephosphinic acid esters of glycols and diols having no hydroxyl groups.Using a molar excess of the diol compound greater than 10 moles per 1mole 1-halo-phospholene-1-oxide is inexpedient due to the need torecycle a large quantity of diol.

The hydroxyl-functional phospholene-1-oxides of formula (I-A) or morespecifically (I-A-1) or (I-A-2) of the present invention have aphosphorus content of about 2-18% by weight and a hydroxyl number ofabout 150-450 mg KOH/g, depending on the 1-halo-phospholene-1-oxide andthe diol taken for the reaction.

It is preferred, for the preparation of the target hydroxyl-functionalphospholene-1-oxides (I-A) or more specifically (I-A-1) or (I-A-2) withthe highest possible phosphorus content, to react non-substituted ormethyl-substituted 1-chloro-phospholene-1-oxides having the highestphosphorus content amongst the 1-halo-phospholene-1-oxides (III), withethylene glycol.

Thus, the compound of formula (I-A-1) having particularly valuableproperties, is that wherein R¹, R³ and R⁴ are each hydrogen, R² ismethyl, Y is —CH₂CH₂—, n is 1 and R⁷ is hydrogen.

Said reactions are carried out at a temperature of between 25° C. and120° C., and preferably between 50° C. and 90° C. Applying a temperaturelower than 25° C. results in a low yield. On the other hand, applying atemperature higher than 120° C. is not advisable since at suchtemperatures undesirable decomposition products may be formed. Inaddition a catalyst can be used to accelerate reaction for example MgCl₂or ZnCl₂.

In a preferred embodiment the reaction of 1-halo-phospholene-1-oxides(III) with an aliphatic diol is carried out in the presence of a strongbase such as sodium hydroxide or potassium hydroxide, in a medium ofboth an organic solvent and an excess aliphatic alcohol. The organicsolvent is selected from aromatic compounds. Especially suitablearomatic solvents are chlorobenzene, ortho-dichlorobenzene, mesitylene,and in particular, toluene and xylene. An effective amount of the baseemployed in the process is in a range of 1-1.2 mol per 1 mol1-halo-phospholene-1-oxides (III), and preferably 1-1.05 mol.

Sodium or potassium hydroxide can be employed in a solid form. Waterresulting from the reaction between the diol and the base should beeliminated from the reaction mixture as much as possible prior to theaddition of 1-halo-phospholene-1-oxides (III).

In a preferred embodiment, the reaction of 1-halo-phospholene-1-oxides(III) with an aliphatic polyol is carried out by varying the degree ofpartial phosphorylation of the polyol. The phosphorus-containing polyolaccording to the present invention comprises at least onephosphorus-containing group. This phosphorus-containing group is a groupof formula (M-A).

wherein:

wherein R¹, R², R³ and R⁴ are as defined and the dashed line indicates adouble bond located between the carbon atom at position 3 and one of thecarbon atoms at positions 2 and 4, provided that each of the two ringcarbon atoms which are not part of the double bond are each bonded toone of the two hydrogen atoms shown in the structural formula (III), andwherein the wavy line indicates a bond to a diol or polyol via an oxygenatom.

The phosphorus-containing polyol of the invention can also comprise twoor more phosphorus-containing groups of formula (III-A), wherein thesephosphorus-containing groups can be identical or different.

The reaction of 1-halo-phospholene-1-oxides (III) with an aliphaticpolyol can be carried out in the presence of an organic base which isselected from, but not limited to, the group of tertiary amines, forexample, triethylamine, pyridine, diisopropyl ethyl amine,1-methylimidazole. The amount of base used is equimolar to1-halo-phospholene-1-oxide (III). The base can also be used in excess tothe 1-halo-phospholene-1-oxide. Said reactions are typically carried outin a medium of inert organic solvent. Suitable solvents for thephosphorylation are, but not limited to, halogenated hydrocarbons, suchas methylene chloride, chloroform or 1,2-dichloroethane. Solvents whichare further suitable are ethers such as dioxane or tetrahydrofuran.Solvents which are further suitable are hydrocarbons such as hexane ortoluene.

In a preferred embodiment the reaction of 1-halo-phospholene-1-oxides(III) with an aliphatic polyol is carried out in the presence of astrong inorganic base such as sodium hydroxide or potassium hydroxide,in a medium of an organic solvent such as chlorobenzene, mesitylene, andin particular, toluene and xylene.

An effective amount of the base employed in the process is in a range of1-1.2 mol per 1 mol 1-halo-phospholene-1-oxides (III), and preferably1-1.05 mol.

Sodium or potassium hydroxide can be employed in a solid form. Waterresulting from the reaction between the polyol and the base should beeliminated from the reaction mixture as much as possible prior to theaddition of 1-halo-phospholene-1-oxides (III).

The amounts of 1-halo-phospholene-1-oxide (III) and polyol can beadjusted so that the desired degree of functionalization is attained.Partial phosphorylation of the polyol can be achieved by using less thanthe stoichiometric amount of the 1-halo-phospholene-1-oxide (III) to thepolyol based on its functionality. In this way, only a portion of the OHgroups in the polyol is reacted with 1-halo-phospholene-1-oxide.

The phosphorus-containing polyol of the present invention has anOH-functionality of from 1 to 5, preferably 2, 3 or 4, and a molecularweight of from about 200 to about 1000. The phosphorus-containingpolyols of the present invention have a phosphorus content of about4-12% by weight and a hydroxyl number of about 20-800 mg KOH/g,depending on the 1-halo-phospholene-1-oxide and the polyol taken for thereaction, and on the molar ratio between them.

The polyol phosphorylation reactions are carried out at a temperature ofbetween 0° C. and 100° C., and preferably between 10° C. and 90° C.Applying a temperature lower than 0° C. results in a low reaction rate.On the other hand, applying a temperature higher than 100° C. is notadvisable since at such temperatures undesirable decomposition productsmay be formed.

The following examples illustrate specific embodiments of both thepreparation of certain compounds of the invention and the utility ofthese compounds as flame retardants in flexible polyurethane foams,rigid polyurethane foams, polyisocyanurate foams, coatings, adhesivesand elastomers.

The novel compounds of the invention are useful as flame retardants. Thenew flame retardants may be used as-is, or as a mixture with halogenatedor non-halogenated products. More preferable are compositions of the newhydroxyl-functional phospholene-1-oxides with reactive brominatedproducts containing a hydroxyl-group. For rigid polyurethane (PU) foamsit is preferred to use a mixture with a brominated product, and forpolyisocyanurate (PIR) foams, it is preferred to use a pure product. Forflexible PU foams it is preferred to use pure halogen-freehydroxyl-functional phospholene-1-oxides of the invention.

A preferred brominated flame retardant to be used according to thepresent invention in combination with hydroxyl-functionalphospholene-1-oxides, comprises one or more tribromophenol-terminatedcompounds represented by Formula (VI)

wherein:

n is an integer in the range between 0 and 5, and more preferably in therange between 0 and 4.

Such compounds can also be successfully dissolved in hydroxyl-functionalphospholene-1-oxides, the liquid composition provided by the presentinvention, without altering the stability of the composition, such thatthe resulting composition retains the form of a solution at ambienttemperature over a long storage period. A commercially availabletribromophenol-terminated compound of formula (VI) is produced by DeadSea Bromine Group under the trade name F-3014.

The weight concentration of the hydroxyl-functional phospholene-1-oxidesrelative to the total weight of the composition is preferably between 10and 60%, and more preferably between 20 and 40%.

It has also been found that tribromoneopentyl alcohol, a flame-retardingagent represented by the structure of Formula (VII):

which is solid at room temperature, can also be successfully dissolvedin hydroxyl-functional phospholene-1-oxides, the liquid compositionprovided by the present invention, without altering the stability of thecomposition, such that the resulting composition retains the form of asolution at ambient temperature over a long storage period. Preferably,the weight concentration of tribromoneopentyl alcohol is in the rangebetween 10 and 60%, and more preferably in the range between 20 and 40%,relative to the total weight of the composition. Tribromoneopentylalcohol is commercially available from Dead Sea Bromine Group under thetrade name FR-513.

The novel composition of the present invention is particularly useful asa flame retardant for polyurethane and polyisocyanurate foams. Asexplained above, the liquid composition provided by the presentinvention is a solution that contains the hydroxyl-functionalphospholene-1-oxides of Formula (I-A, or more specifically (I-A-1) or(I-A-2)) or (I-B) in combination with the compound of Formula (VI), orseparately with tribromoneopentyl alcohol (VII), and preferably as asolute of the hydroxyl-functional phospholene-1-oxides of Formulae (I-A,or more specifically (I-A-1) or (I-A-2)) or (I-B) with both thecompounds of Formula (VI) and Formula (VII), and may therefore bedirectly added to the liquid mixture of reactants used for preparingpolyurethane and polyisocyanurate foams, whereby the blending operationof said mixture is considerably simplified and a uniform distribution ofthe components to be reacted is readily obtained in said mixture.

In another embodiment herein the brominated flame retardant is selectedfrom the group consisting of brominated bisphenol A compounds,brominated bisphenol S compounds, brominated bisphenol F compounds,brominated bisphenol A carbonate oligomers, brominated bisphenol A epoxyresins, end-capped brominated bisphenol A epoxy resin, aliphaticbrominated alcohols and glycols, dibromoneopentyl glycol, brominatedphthalates and tetrabromophthalate diols, brominated phosphates,brominated phenols, brominated phthalic acids, and combinations thereof.

The amount of the brominated flame retardant to be used according to thepresent invention varies depending on the relationship between theextent of the flame retardation required of polyurethane foam andphysical properties. However, the brominated flame retardant is usuallyused in an amount of 1 to 50 parts by weight based on 100 parts byweight of polyurethane foam. In an amount less than 1 part by weight,desired flame retardancy cannot be imparted. Amounts exceeding 50 partsby weight bring about sufficient flame retardancy but may impair thephysical properties of the molded or formed product of the resultingfoam. Amounts outside the above-described range are therefore notpreferred. From the viewpoint of keeping good balance between the flameretardancy and physical properties, the amount practically falls withina range of 3 to 30 parts. Depending on the end use application, two ormore brominated flame retardants can be used in combination.

Thus, the new flame retardant compositions of the present invention maybe used as preformed concentrates that can be added to standardformulations suitable for obtaining rigid polyurethane foams (bycontinuous, discontinuous or spray methods) or polyisocyanurate foams.

In another aspect, the present invention provides a composition of thenovel hydroxyl-functional phospholene-1-oxides (I-A) or morespecifically (I-A-1) or (I-A-2) or I-B with either halogenated ornon-halogenated products (or both).

The weight ratio between the compound of Formula (I-A-1) or (I-A-2) outof general formula I-A and the other products in the flame-retardantcomposition of the invention is between 1:9 and 9:1, and more preferablybetween 30 and 70%. The brominated flame retardants, for exampletribromoneopentyl alcohol (FR-513) and tribromophenol-terminatedcompounds represented by Formula (VI), may be included in thecomposition of the invention, such that the weight concentrations of thehydroxyl-functional phospholene-1-oxides of the invention,tribromoneopentyl alcohol (VII) and tribromophenol-terminated compoundsrepresented by Formula (VI) in the flame-retardant composition of theinvention, are in the ranges from 10 to 50 wt %, 10 to 50 wt % and 10 to50 wt %, respectively.

The novel compounds of the present invention are highly efficient flameretardants when incorporated into rigid, semi-rigid, or flexiblepolyurethane foams, polyisocyanurate (PIR) foams, polyurethane coatings,polyurethane adhesives and polyurethane elastomers. It should be notedthat the compounds of the invention are useful over a broad IsocyanateIndex (abbreviated herein MDI or TDI). The index refers to the ratio ofisocyanate practically used in the formulation vs. the theoreticalstoichiometric amount of isocyanurate required, expressed inpercentages.

The rigid or semi-rigid polyurethane or polyisocyanurate foams contain atypical flame retardant amount of the composition of this invention.Typically, the compositions of this invention are used in amountsproviding a total phosphorus concentration in the polymer in the rangeof 0.3 to 15 wt %, based on the total weight of the polymer. Preferably,the total phosphorus concentration in the polymer is in the range 1 to10 wt %, and more preferably in the range of 2 to 5 wt %, based on thetotal weight of the polymer. Most preferably, the amounts used of theflame retardants of this invention are at least sufficient to meet thecurrent requirements of the DIN 4102 B2 test.

The flexible polyurethane foams contain a typical flame retardant amountof the composition of this invention. Typically, the compositions ofthis invention are applied in amounts that provide a total phosphorusconcentration in the polymer in the range of 0.3 to 15 wt %, based onthe total weight of the polymer. Preferably, the total phosphorusconcentration in the polymer is in the range of 1 to 10 wt % and morepreferably, in the range of 1.5 to 5 wt %, based on the total weight ofthe PU polymer. Most preferably, the amounts used of the flameretardants of this invention are at least sufficient to meet the currentrequirements of the flammability Test Method MVSS 302.

By suitable choice of components and conditions, foams are made whichvary in properties from the soft flexible type used in upholsteryapplications to the hard rigid type used as insulation/structuralmembers. Thus, flexible foams are generally made from polymeric diols ortriols having hydroxyl numbers of from 20 to 80 using water as theprincipal foaming agent. The much higher crosslink density required inrigid foams is provided by the use of higher functionality polyolsand/or polyisocyanates and here the principal foaming agent is usually ahalogenated hydrocarbon such as trichlorofluoromethane.

Between the extremes of flexibility on the one hand and rigidity on theother, there exists another useful type of foam generally classified assemi-rigid. These foams, which are used as shock-absorbing materials inthe passenger compartments of automobiles and elsewhere, are usuallymade by reacting a polyisocyanate with a mixture of a flexible foampolyol and a crosslinking agent such as trimethylolpropane.

Whilst the production of all polyurethane foams, flexible, rigid orsemi-rigid, involves the same basic chemical reaction, that betweenisocyanate groups and hydroxyl groups, each type of foam presentsdifferent problems to the manufacturer. The differences are oftenassociated with the balance which must always be achieved between gasgeneration and polymer gelation. Clearly, for example, the balance in awater-blown flexible foam system is different from that in asolvent-blown highly crosslinked rigid foam system. Many of theseproblems can be solved, at least partially, by appropriate choice ofauxiliary agents, for example catalysts, surfactants, foam stabilizersand the like.

Flexible polyurethane foams as used herein is made using a polyol havinga 3,000 to about 6,000 molecular weight polyol as described herein,e.g., a polyether triol prepared by the addition of propylene oxide toglycerol. A flexible polyurethane foam as used herein is characterizedby having a core impact resilience of at most 30% and a glass transitionpoint of from −80° C. to −60° C. Here, the flexible polyurethane foampreferably has a hard segment content of at most 40 mass %. Conventionalflexible polyurethane foam having a bulk foam density of 2.5 pounds percubic foot (PCF) or lower and having a foam hardness or IFD (measured inaccordance with test method ASTM 3574-Test B1) in a range of 10 to 90lb/50 in².

Rigid polyurethane foam as used herein is made from more highlybranched, lower equivalent weight polyether polyols with functionalitiesas high as 8. In a rigid polyurethane foam a higher concentration ofaromatic polyisocyanate is needed than in a flexible foam. A rigidpolyurethane foam obtainable by the method of the present inventionpreferably has a core density of from 10 to 50 kg/m³, more preferablyfrom 20 to 40 kg/m³.

Rigid foams have been used in the auto and other industries for a numberof purposes. For example, rigid foams have been used for structuralreinforcement, preventing corrosion and damping sound and vibration.These foams are typically formed by applying a reactive foam formulationto a part and allowing the formulation to foam in place. The part isoften already assembled onto a vehicle when the foam is applied. Thismeans that the foam formulation must be easy to mix and dispense, mustcure rapidly before it runs off the part, and preferably initiatescuring at moderate temperatures. To minimize worker chemical exposure,the formulation is preferably is low in volatile organic compounds,especially volatile isocyanates and amines. The individual componentsare preferably storage-stable at room temperature for an extendedperiod.

The term semi-rigid as applied to foams is a standard term used in theart. Generally such foams have a glass transition temperature (Tg)between rigid and flexible foams.

The compositions of the invention can be combined with the polyolcomponent and/or the polyisocyanate component or catalyst and one ormore of the flame retardant materials of Formulae (IA), (I-A-1), (I-A-2)and (I-b) described herein which may be metered and pumped into a commonmixing vessel, and then the resulting mixture may be easily be moved tothe polymerization site for use in molds, slab stock operations, etc.

The compositions of the invention herein may also be admixed with thepolyol reactant before it is combined with the polyisocyanate reactant.It is also within the scope of the invention to mix the flame retardantmaterials with the polyisocyanate before combining such mixture with thepolyol reactant. However, if the polyisocyanate and the aforementionedflame retardant materials are mixed and allowed to stand at roomtemperature for a substantial period of time, reaction may occur.

The flame retardant materials of Formulae (IA), (I-A-1), (I-A-2) and(I-b) described herein may be described as isocyanate-reactive(NCO-reactive) materials, i.e., they are reactive with the isocyanatesthrough the hydroxyl group(s).

The polyols used in making the polyurethane foams and/orpolyisocyanurate foams described herein (be they, flexible, semi-rigidor rigid) can include any organic polyol, including diols, polyols, andpolyether, polyester, polyesteramide polyols having hydrogen atoms thatare reactive with isocyanates may be used. Generally, these materialshave molecular weights ranging from about 62 to about 5,000 and havefrom 2 to about 10 or more hydroxyl groups per molecule and weightpercent hydroxyl contents ranging from about 0.5 to about 25%. Thegenerally have hydroxyl numbers of from about 50 to as high as 500 oreven 700.

In the polyester-polyol type of reactant the acid number should be lessthan 10 is usually as close to 0 as possible. These materials arereferred to conveniently as the “polyol” reactant. The useful activehydrogen-containing polyols include the large family of adduct compoundswhich result when ethylene oxide, propylene oxide, 1,2- and 2,3-butyleneoxide, or other alkylene oxides are added to such active hydrogencompounds such as glycols and polyols presented by ethylene glycol,propylene glycol, glycerine, methyl glucoside, sucrose, sorbitol,hexanetriol, trimethylol propane, pentaerythritol as well as variousalkylamines and alkylenediamines, and polyalkylenepolyamines and thelike. Various amounts of these alkylene oxides may be added to the basedpolyol or amine molecules referred to, depending upon the intended useof the polyurethane. For example, when a final polyurethane is desiredwhich is flexible, one would use more alkylene oxide than for a morerigid polyurethane.

For example, a polyol for use in making flexible foams could be wellrepresented by glycerine to which sufficient propylene oxide was addedto give a final hydroxyl content of about 1.7%. Such a material wouldhave a molecular weight of about 3,000 and have a molar ratio ofglycerine to propylene oxide of about 1 glycerine to 50 propylene oxide.This technique of controlling rigidity or flexibility by selection ofthe polyol molecule and the subsequent amount of alkylene oxide added iswell known to those in the art.

In addition to the glycols and the like which can serve as the basepolyol molecule for addition of the alkylene oxides and thus yield the“polyol” molecule for reaction with the isocyanate, one can use astarting molecule which contains primary and/or secondary amine groupswhich have hydrogen reactive toward alkylene oxides. Here also, thequantity of alkylene oxide added depends on the intended uses of thefinal polyurethane products. Again, for flexible products where morealkylene oxide would be used to product polyols with lower hydroxylcontent, such as from about 0.1% to about 5% or 10%, than for more rigidpolyurethanes wherein polyols having weight percent hydroxyl content offrom about 10% to about 15% or 20%, typically, 10% to 12%, are oftenused.

Representative amines which may serve as active-hydrogen containingmolecules for reaction with epoxides are those having from 1 to about 6or more amino nitrogens, examples of which are ethyl amine, ethylenediamine, diethylenetriamine, triethylenetetramine,tetrapropylenepentamine and other linear saturated aliphatic alkyleneamines, the important requirement being at least two, and preferablymore, say 3 to 8 or 10 active hydrogen sites to which the alkylene oxidemay be added.

It is also well known to use the hydroxyl bearing molecules which havebeen prepared by esterification type reactions from polyfunctional acidsor anhydrides and polyfunctional alcohols as the active hydrogencompounds used in preparing the polyurethane systems. These compoundsare often called polyester polyols. Typical acids used in making thesepolyester polyols are maleic, phthalic, succinic, fumaric,tetrahydrophthalic, chlorendic, and tetrachlorophthalic acids. Typicalpolyols are ethylene, propylene, butylene, diethylene, and dipropylene,glycols, and polyethylene, polypropylene, glycols and glycerine,trimethylol propane, hexanetriol, pentaerythritol, sorbitol and thelike. Where available the above mentioned acids may be used in theanhydride form if desired.

In making the polyester-polyols, any of the various polyfunctional acidsor anhydrides or mixtures thereof are caused to react with any of theglycols or polyols or mixtures thereof, using a stoichiometric excess ofthe hydroxyl groups such that the final polyol product containspredominantly hydroxyl end groups. The degree of hydroxyl functionalityand the percent hydroxyl is easily varied to provide the desired polyolsby technology and techniques which are known to those skilled in theart.

In the art and technology of making polyurethanes, it is also known toemploy what is called prepolymer techniques. This is a technique whereinpart of the reaction involved in making polyurethane is carried outyielding a prepolymer of increased molecular weight and with eitherresultant end groups of hydroxyls or isocyanates depending on thestoichiometric used in making this prepolymer. This prepolymer is thenused to prepare the final polyurethane product by reacting it witheither a polyisocyanate or polyol, depending on, as mentioned above,whether the terminal groups of the prepolymer are hydroxyls orisocyanates, respectively.

Broadly, any of the prior art polyesters,polyisocyanate-modified-polyester prepolymers, polyesteramides,polyisocyanate-modified-polyesteramides, alkylene glycols,polyisocyanate-modified alkylene glycols, polyoxyalkylene glycols,polyisocyanate-modified polyoxyalkylene glycols, etc., having freereactive hydrogens and especially hydroxyl groups may be employed forthe production of the polyurethanes or polyisocyanurates describedherein.

Examples of isocyanates which can be used include those having two ormore isocyanate groups which have heretofore been used for makingflexible polyurethane foams. Examples of such isocyanate compoundsinclude aromatic isocyanates, aliphatic isocyanates and alicyclicisocyanates, as well as mixtures of two or more of such isocyanates, andmodified isocyanates obtained by the modification of such isocyanates.Specific examples of such isocyanates are toluene diisocyanate,diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate(crude MDI), xylylene diisocyanate, isophorone diisocyanate andhexamethylene diisocyanate; and modified products of suchpolyisocyanates, such as carbodiimide-modified products, biuret-modifiedproducts, dimers and trimers. Prepolymers with terminal isocyanategroups obtained from such isocyanates and active hydrogen-containingcompounds can also be used.

In one embodiment, the isocyanate index range for flexible polyurethanefoams can be from about 130 to about 80, more preferably, from about 120to about 90 and most preferably from about 115 to about 95.

As the blowing agent in the flexible polyurethane foam-formingcomposition of the present invention, known blowing agents heretoforeused in such compositions are suitably selected according to theproperties required of the foamed product.

In the present invention, a cross-linking agent is also used as the caserequires.

As the cross-linking agent, a compound having at least two functionalgroups having active hydrogen, such as hydroxyl groups, primary aminogroups or secondary amino groups is preferred. However, in a case wherea polyol compound is used as the cross-linking agent, the following istaken into account. Namely, a polyol compound having a hydroxyl value ofat least 50 mg KOH/g and more than four functional groups, is consideredto be the cross-linking agent, and a polyol which does not satisfy this,is considered to be any one of polyols of the above-mentioned polyolmixture (polyol (1), (2) or other polyol). Further, two or morecross-linking agents may be used together. As specific examples, apolyhydric alcohol such as dextrose, sorbitol or sucrose; a polyolhaving an alkylene oxide added to a polyhydric alcohol; an aminecompound such as monoethanolamine, diethanolamine, ethylenediamine,3,5-diethyl-2,4 (or 2,6)-diaminotoluene (DETDA),2-chloro-p-phenylenediamine (CPA), 3,5-bis(methylthio)-2,4 (or2,6)-diaminotoluene, 1-trifluoromethyl-4-chloro-3,5-diaminobenzene,2,4-toluenediamine, 2,6-toluenediamine,bis(3,5-dimethyl-4-aminophenyl)methane, 4,4′-diaminodiphenylmethane,m-xylylenediamine, 1,4-diaminohexane, 1,3-bis(aminomethyl)cyclohexane orisophoronediamine; and a compound obtained by adding an alkylene oxidethereto, may, for example, be mentioned.

When the above cross-linking agent is used, even in a case where, forexample, a large amount of a blowing agent is used to produce a flexiblefoam having a low density, the foaming stability will be good, and itwill be possible to produce such a flexible foam. Especially when apolyol having a high-molecular weight is used, it is possible to producea flexible foam having a low density which used to be considereddifficult to foam. Further, when the cross-linking agent is used, thedurability will be improved, as compared with a case where it is notused. In a case where a polyol having a high-molecular weight is used asin the present invention, the foaming stability can readily be improvedparticularly when a compound having a relatively high-molecular weight,such as a molecular weight of at least 4000, is used.

Water is a typical example of such a blowing agent; other examplesinclude methylene chloride, n-butane, isobutane, n-pentane, isopentane,dimethyl ether, acetone, carbon dioxide, and the like. Depending on thedesired density and other properties of the foamed polyurethane, theseand other blowing agents can be used alone or in combinations of two ormore in a manner known in the art.

The amount of blowing agent to be used is not particularly limited butwill ordinarily range from 0.1 to 20 parts by weight per 100 parts byweight of the polyol component of the foam-forming composition.Preferably, the amount of blowing agent(s) will be such as to provide afoam density of from 0.8 to 2.5 pounds per cubic foot, and preferablyfrom 0.9 to 2.0 pounds per cubic foot.

The polyurethane foam-forming composition herein can preferably containany of the catalysts, and combination of catalysts, heretofore known orused for the production of polyurethane foams. Examples of usefulcatalysts include sodium hydroxide, sodium acetate, tertiary amines ormaterials which generate tertiary amines such as trimethylamine,triethylene diamine, N-methyl morpholine, N,N-dimethyl cyclohexylamine,and N,N-dimethyl aminoethanol. Also applicable are metal compounds suchas hydrocarbon tin alkyl carboxylates, dibutyl tin diacetate, dibutyltin dioctoate dibutyl tin dilaurate and stannous octoate; as well asother compounds intended to promote trimerization of the polyisocyanatesuch as, 2,4,6-tris(N,N-dimethylamino-methyl)phenol,1,3,5-tris(N,N-dimethyl-3-aminopropyl)-S-hexahydrotriazine, potassiumoctoate, potassium acetate and catalysts such as DABCO TMR® and POLYCAT43®.

Many other kinds of catalysts can be substituted for those listed above,if desired. The amount of catalyst used can advantageously range from0.05 to 5 weight percent or more based on the total weight of polyol inthe foam-forming mixture.

The isocyanate (NCO) index which is applied in making the flexible foamaccording to the present invention is 95-125 and preferably 100-120. TheNCO index which is applied in making the semi-rigid foam according tothe present invention is 126-180 and preferably 130-175. The NCO indexwhich is applied in making the rigid foam according to the presentinvention is 181-350 and preferably 200-300. It is commonly understoodthat the NCO index of polyurethane foams is from about 80-130 and theNCO index of isocyanurate foams is from about 200-350.

The densities of the flexible foams may range of from 14-80 andpreferably 16-55 and most preferably 20-40 kg/m³.

The densities of the semi-rigid foams may range of from 8 to 180 andpreferably 8-80 and most preferably 8-48 kg/m³.

The densities of the rigid foams may range of from 8 to 180 andpreferably 8-80 and most preferably 8-48 kg/m³.

Surfactants, including organic surfactants and silicone basedsurfactants, may be added to serve as cell stabilizers. Somerepresentative materials are sold under the designations SF-1109, L-520,L-521 and DC-193, which are, generally, polysiloxane polyoxylalkyleneblock copolymers. Also included are organic surfactants containingpolyoxy-ethylene-polyoxybutylene block copolymers. It is particularlydesirable to employ a minor amount of a surfactant to stabilize thefoaming reaction mixture until it cures. Other surfactants that may beuseful herein are polyethylene glycol ethers of long-chain alcohols,tertiary amine or alkanolamine salts of long-chain allyl acid sulfateesters, alkylsulfonic esters, alkyl arylsulfonic acids, and combinationsthereof. Such surfactants are employed in amounts sufficient tostabilize the foaming reaction against collapse and the formation oflarge uneven cells. Typically, a surfactant total amount from about 0.2to about 3 wt %, based on the formulation as a whole, is sufficient forthis purpose. However, it may be in some embodiments desirable toinclude some surfactants, e.g., DABCO DC-5598, available from AirProducts and Chemicals, Inc., in a higher amount. In view of this asurfactant may be included in the inventive formulations in any amountranging from 0 to 6 wt %, based on the polyol component.

Finally, other additives such as fillers and pigments may be included inthe polyurethane foam formulations described herein. Such may include,in non-limiting embodiments, barium sulfate, calcium carbonate,graphite, carbon black, titanium dioxide, iron oxide, microspheres,alumina trihydrate, wollastonite, prepared glass fibers (dropped orcontinuous), polyester fibers, other polymeric fibers, combinationsthereof, and the like. Those skilled in the art will be aware withoutfurther instruction as to typical and suitable means and methods toadapt the inventive formulations to produce rigid polyurethane foamsthat, though still falling within the scope of the claims appendedhereto, exhibit or benefit from desired property and/or processingmodifications.

The polyurethane and/or polyisocyanurate foams described herein, be theybe flexible, semi-rigid or rigid, can be utilized in the constructionand formation of various articles such as furniture, bedding, automotiveseat cushions, panel insulation for wall panel and roof panelconstruction, and pour-in-place and spray foam insulation for wallpanels and roof panels.

Flexible slabstock polyurethane foam can be used for furniture, e.g.,upholstered furniture, such as cushions, backs and arms, the automotiveindustry, such as seat and back cushions for automobiles and trucks,public transport seating, such as busses and airplanes, as well as inany of tractor, bicycle and motorcycle seats, and bedding such asmattresses, as sound insulation materials, automobile interiorcomponents such as an arm rest, a steering wheel and a shift lever knob,shoe soles, and sporting goods. Articles such as an automobile steeringwheel and a shoe sole which require high wear resistance, for example,are usually made of a molded member covered by a skin on the surfacethereof (or on the bottom in the case of shoe), with the inner portion(core) desirably having a lower density for better touch feeling.

Saddles of bicycles are also typically covered by a skin because a highstrength is required of the surface with which the body of the ridermakes contact and the portion where the saddle is mounted on thebicycle, with the core desirably having a lower density and softness forbetter ride comfort. In order to finish the painted surface with betterappearance, the surface layer is required to have a high density.

Rigid and semi-rigid polyurethane foam has many applications such as animitation lumber and a structural material. In addition, rigidpolyurethane foam can be use in applications such as insulation,construction and packaging; microcellular froth polyurethane foam suchas footwear and gasketing; and viscoelastic (“memory”) polyurethane foamchemistries, in air filters and as decorative facings for speakers, foamsheets produced on laminating machines with suitable facings or vaporbarriers, tank and pipe insulation, applied by sheet, molding and spraytechniques, insulation for refrigerators, freezers, water heaters, usein flotation and packaging. The insulation can also comprise window anddoor insulation.

The insulation can be used in any structural component such as a roof orwall. There is also provided a roof structure comprising joistssupporting a structural deck and insulation panels such as thosedescribed above positioned above the structural deck, wherein optionallycoverboards are positioned thereover, and then a water-proof layer suchas built-up roofing or bitumen, or the like is applied thereover, andthen there is applied thereover conventional roof coverings such asshingles, tiles, and the like.

There is also provided a wall structure comprising a frame coupledtogether with structural support members such as wood, steel or concretebeams, a single layer or a plurality of rigid foam insulation boards,e.g., polyisocyanurate foam boards, affixed to the exterior of theframe, for form a continuous outside wall, wherein such coupling andaffixing is done with fasteners such as nails, screws, rivets and thelike, and wherein there is space formed between the structural supportmembers, and insulation is located within the space so formed, andoptionally wall boards are fastened to the interior of the frame to forman internal surface.

EXAMPLES

The viscosity measurements provided herein were conducted at 25° C. bymeans of a Canon Fenske viscometer.

Preparation Example 1 Preparation of a Mixture of Isomers of1-(2-hydroxy-propoxy)-3-methyl-phospholene-1-oxides and1-(1-methyl-2-hydroxyethoxy)-3-methyl-phospholene-1-oxides

A 2 liter reactor, equipped with a mechanical stirrer, reflux condenser,dropping funnel and thermometer, was charged with an isomeric mixture(150 g, 1.14 mol) composed of 55%1-hydroxy-3-methyl-3-phospholene-1-oxide and 45%1-hydroxy-3-methyl-2-phospholene-1-oxide, based on ³¹P NMR. Further,propylene oxide (105 g, 1.81 mol) was added to the reactor contents at60° C. over a period of 2 h. The reaction was exothermic and was kept at80° C. for an additional 2 h until the conversion of the1-hydroxy-3-methyl-phospholene-1-oxides was complete (confirmed by ³¹PNMR). The propylene oxide was evaporated and the residue was distilledusing a wiped film evaporator under vacuum (1 mbar) and the targetfraction was collected at a vapor temperature of 110-170° C. A clearcolorless liquid (173 g) was obtained. The yield was 80% with respect tothe starting 1-hydroxy-3-methyl-phospholene-1-oxides. The product was amixture of four isomers of hydroxyl-functional3-methyl-phospholene-1-oxides. ³¹P NMR (CDCl₃): δ=76.7-78.1 (m). Thefinal product had a phosphorus content of 15.2%, a hydroxyl number of286 mg KOH/g, an acid number of 0.4 mg KOH/g and a viscosity of 272 cP.

Preparation Example 2 Preparation of a Mixture of Isomers of1-(2-hydroxy-propoxy)-phospholene-1-oxides and1-(1-methyl-2-hydroxyethoxy)-phospholene-1-oxides

A 2 liter reactor, equipped with a mechanical stirrer, reflux condenser,dropping funnel and thermometer, was charged with an isomeric mixture(199 g, 1.68 mol) composed of 59% 1-hydroxy-3-phospholene-1-oxide and41% 1-hydroxy-2-phospholene-1-oxide, based on ³¹P NMR. Further,propylene oxide (117 g, 2.01 mol) was added to the reactor contents at60° C. over a period of 2 h. The reaction was exothermic and was kept at80° C. for an additional 7 h until the conversion of the1-hydroxy-phospholene-1-oxides was complete (confirmed by ³¹P NMR). Thepropylene oxide was evaporated and the residue was distilled on wipedfilm evaporator under vacuum (1 mbar) and the target fraction wascollected at a vapor temperature of 110-170° C. A clear colorless liquid(255 g) was obtained. The yield was 85% with respect to the starting1-hydroxy-phospholene-1-oxides. The product was a mixture of fourisomers of hydroxyl-functional phospholene-1-oxides. ³¹P NMR (CDCl₃):5=77.1-78.8 (m). The final product had a phosphorus content of 16.5%, ahydroxyl number of 321 mg KOH/g, an acid number of 0.4 mg KOH/g andviscosity 172 cP.

Preparation Example 3—Reaction Between1-hydroxy-3-methyl-phospholene-1-oxides and 1,2-epoxybutane

A 100 ml reactor, equipped with a stirrer, reflux condenser, droppingfunnel and thermometer, was charged with an isomeric mixture (9.2 g,0.07 mol) of 37% 1-hydroxy-3-methyl-3-phospholene-1-oxide and 63%1-hydroxy-3-methyl-2-phospholene-1-oxide, based on ³¹P NMR.1,2-epoxybutane (12 g, 0.17 mol) was then added dropwise to the reactorcontents at 25° C. over a period of 15 min. The reaction was exothermicand the mixture was held at 80° C. for an additional 5 h until theconversion of the 1-hydroxy-3-methyl-phospholene-1-oxides was complete(confirmed by ³¹P NMR). The excess 1,2-epoxybutane was evaporated at 95°C. under vacuum (˜1 mbar). A clear colorless liquid (14.3 g) wasobtained. The product was a mixture of four isomers ofhydroxyl-functional 3-methyl-phospholene-1-oxides. ³¹P NMR (CDCl₃):δ=76.1-77.2 (m). The final product had an acid number of 7.5 mg KOH/g.

Preparation Example 4—Reaction Between1-hydroxy-3-methyl-phospholene-1-oxides and trimethylolpropanetriglycidyl ether

A 1 liter reactor, equipped with a mechanical stirrer, reflux condenser,dropping funnel and thermometer, was charged with an isomeric mixture(84.7 g, 0.64 mol) of 1-hydroxy-3-methyl-phospholene-1-oxides andtrimethylolpropane triglycidyl ether (96 g, 0.318 mol). The reactionmixture was held at 60° C. for 12 h until the conversion of the1-hydroxy-3-methyl-phospholene-1-oxides was complete (confirmed by ³¹PNMR). 300 g DCM was then added. The solution was washed with 200 g aq.2% Na₂CO₃ and twice with 150 g distilled water. Evaporation of the DCMfrom the washed product resulted in a very viscous liquid (112 g).³¹P-NMR (CDCl₃): δ=83.6-85.3 (m). The final product had a phosphoruscontent of 9.2%, a hydroxyl number of 251 mg KOH/g and an acid number of0.18 mg KOH/g.

Preparation Example 5—Reaction Between1-hydroxy-3-methyl-phospholene-1-oxides and styrene oxide

A 1 liter reactor, equipped with a mechanical stirrer, reflux condenser,dropping funnel and thermometer, was charged with an isomeric mixture(124.1 g, 0.94 mol) of 1-hydroxy-3-methyl-phospholene-1-oxides, styreneoxide (188.5 g, 1.57 mol) and 100 ml toluene. The reaction wasexothermic and the mixture was held at 50° C. for 12 h until theconversion of the 1-hydroxy-3-methyl-phospholene-1-oxides was nearlycomplete (confirmed by ³¹P NMR). The toluene and excess styrene oxidewere evaporated at 95° C. under vacuum (˜1 mbar). A clear colorlessliquid (245 g) was obtained. The product was a mixture of four isomersof hydroxyl-functional 3-methyl-phospholene-1-oxides. ³¹P-NMR (CDCl₃):δ=73.7-75.7 (m).

Preparation Example 6—Reaction Between1-hydroxy-3-methyl-phospholene-1-oxides and Epoxidized Soy Bean Oil(ESBO)

A 100 ml reactor, equipped with a magnetic stirrer, thermometer andreflux condenser, was charged with an isomeric mixture (15.4 g, 0.11mol) of 1-hydroxy-3-methyl-phospholene-1-oxides, ESBO (19.4 g, 0.0194mol) and 20 ml toluene. The reaction mixture was held at 60° C. for 18 huntil the conversion of the 1-hydroxy-3-methyl-phospholene-1-oxides wascomplete (confirmed by ³¹P NMR). The reaction mixture was washed withaq. 2% NaOH (20 g) and twice with 30 g distilled water. The toluene wasevaporated at 95° C. under vacuum (˜1 mbar). A waxy colorless liquid (34g) was obtained. ³¹P-NMR (CDCl₃): δ=79.75-80.9 (m).

Preparation Example 7—Reaction Between1-chloro-3-methyl-phospholene-1-oxides and Ethylene Glycol MonosodiumSalt

A 2 liter reactor, equipped with a mechanical stirrer, thermometer,Dean-Stark trap and reflux condenser with a nitrogen inlet, was chargedwith ethylene glycol (1004 g, 16.2 mol), NaOH (114.3 g, 2.85 mol) and300 ml toluene. The solution was heated at reflux for 1.5 h, duringwhich time water (51 g) distilled off. The solution was then cooledunder nitrogen to 30° C. and an isomeric mixture of1-chloro-3-methyl-3-phospholene-1-oxide and1-chloro-3-methyl-2-phospholene-1-oxide (406.4 g, 2.7 mol) was addeddropwise over a period of 2 h. An exotherm was observed. The temperaturewas maintained at 65° C. for an additional 2 h. Subsequently, thetoluene and the excess ethylene glycol were distilled off under vacuum(˜1 mbar). Dichloromethane (200 ml) was added at ambient temperature,and the mixture was filtered to remove the NaCl formed. The product wasfurther distilled under vacuum (˜1 mbar) and the target fraction wascollected at a vapor temperature of 103-166° C. A clear yellowish liquid(309 g) was obtained. The yield was 65% with respect to the starting1-chloro-3-methyl-phospholene-1-oxides. The product was a mixture of twoisomers of hydroxyl-functional 3-methyl-phospholene-1-oxides. ³¹P-NMR(CDCl₃): δ=78.9-79.1 (m). The final product had a phosphorus content of15.3%, and an acid number of 1.28 mg KOH/g.

Preparation Example 8—Reaction Between1-chloro-3-methyl-phospholene-1-oxides and Diethylene Glycol MonosodiumSalt

A 1 liter reactor, equipped with a mechanical stirrer, thermometer,Dean-Stark trap, and reflux condenser with a nitrogen inlet, was chargedwith diethylene glycol (440 g, 4.15 mol), NaOH (27.7 g, 0.69 mol) and300 ml toluene. The solution was heated at reflux for 1.5 h, duringwhich time water (12 g) distilled off. Then, the solution was cooledunder nitrogen to 30° C. and an isomeric mixture of1-chloro-3-methyl-3-phospholene-1-oxide and1-chloro-3-methyl-2-phospholene-1-oxide (98.12 g, 0.65 mol) was addeddropwise over a period of 2 h. An exotherm was observed. The temperaturewas maintained at 65° C. for an additional 2 h. Subsequently, thetoluene and the excess diethylene glycol were distilled off under vacuum(˜1 mbar). Dichloromethane (200 ml) was added at ambient temperature andthe mixture was filtered to remove the NaCl formed. The product wasfurther distilled under vacuum (˜1 mbar) to give a clear yellowishliquid (86 g). The yield was 60% with respect to the starting1-chloro-3-methyl-phospholene-1-oxides. The product was a mixture of twoisomers of hydroxyl-functional 3-methyl-phospholene-1-oxides. ³¹P-NMR(CDCl₃): δ=77.36-78.3 (m). The final product had a phosphorus content of13.5%, a hydroxyl number of 267 mg KOH/g and an acid number of 1.4 mgKOH/g.

Preparation Example 9—Reaction Between1-chloro-3-methyl-phospholene-1-oxides and an Aliphatic TrifunctionalPolyol with Mw 500

A 1 liter reactor, equipped with a mechanical stirrer, thermometer,dropping funnel, and reflux condenser, was charged with an aliphaticpolyol (109.9 g, 0.22 mol), triethylamine (70.7 g, 0.7 mol) and 500 mlanhydrous DCM. The mixture was cooled to 5° C. and an isomeric mixtureof 1-chloro-3-methyl-3-phospholene-1-oxide and1-chloro-3-methyl-2-phospholene-1-oxide (99.3 g, 0.66 mol) was addeddropwise, while maintaining the temperature below 10° C. After theaddition was complete, the reaction mixture was heated at reflux for 3h. The final mixture was filtered, then washed with aq. 0.5% NaOH (500g) and water (400 g). The washed organic phase was evaporated undervacuum at 95° C. to give 142 g of a yellowish waxy liquid. The yield was76% with respect to the starting 1-chloro-3-methyl-phospholene-1-oxides.

³¹P-NMR (CDCl₃): δ=76.5-77.0 (m). The final product had a phosphorouscontent of 9.7%, a hydroxyl number of 30.3 mg KOH/g and an acid numberof 0.3 mg KOH/g sample.

Preparation Example 10—Reaction Between1-chloro-3-methyl-phospholene-1-oxides and an Aliphatic TrifunctionalPolyol with Mw ˜300

A 0.5 liter reactor, equipped with a mechanical stirrer, thermocouple,N₂ inlet, dropping funnel, and reflux condenser, was charged with andried aliphatic polyol (60 g, 0.2 mol), 75.7 g of triethylamine and 250ml anhydrous DCM. The mixture was cooled to 2° C. and an isomericmixture of 1-chloro-3-methyl-3-phospholene-1-oxide and1-chloro-3-methyl-2-phospholene-1-oxide (103.5 g, 0.69 mol) was addeddropwise over ˜2 h, while maintaining the temperature below 5° C. Afterthe addition was completed, the reaction mixture was heated at refluxfor 2 h. The solid was filtered off, solution was washed with water,Na₂CO₃ 16% solution and with water again to give pH=7. The product(101.9 g, 79% of yield) was obtained after DCM evaporation under reducedpressure. The final product had a phosphorous content of 13.4%, ahydroxyl number of 30.1 mg KOH/g and an acid number of 0.3 mg KOH/gsample.

The application of the new compounds of the present invention isdemonstrated through their use as flame retardants in standardformulations for rigid polyurethane foams (Application Example 1) andfor rigid polyisocyanurate foams that have an MDI Index of 300%(Application Example 2). In addition to the flame retardant, thefollowing components were used in the preparation of the foams:

Polyol Components Used for Spray Foam Production (101% Index):

1. Terate HT5100—Aromatic Polyester polyols having a hydroxyl value of295 mg KOH/g available from Invista.2. JEFFOL R 425X—Polyether polyol having a hydroxyl value of 425 mgKOH/g available from Huntsman.

Polyol Components Used for PIR (300% Index) Production:

Kosa Terate 2541—Aromatic Polyester polyols having a hydroxyl value of234 mg KOH/g and is available from Invista.

Ancillary chemicals Polycat 77N-[3-(Dimethylamino)propyl]-N,N′,N′-trimethyl- propane-1,3-diamineavailable from Air Products. DABCO BL-11N,N,N′,N′-Tetramethyl-2,2′oxybis(ethylamine), amine catalyst availablefrom Air Products DC 193 Silicone surfactant available from Air ProductsBicat 8210 Bismuth tris(2-ethylhexanoate) available from ShepardChemical DMCHA Dimethylcyclohexylamine Dabco TMR302,4,6-Tris(dimethylaminomethyl) phenol - Amine catalyst available fromAir Products Tegostab B8460 Polyether-modified polysiloxane surfactantavailable from Evonik Kosmos 75 Potassium-2-ethyl hexanoate catalystavailable from Evonik HFC-245fa Blowing agent available from HoneywellPentane Blowing agent Isocyanate MDI Polymeric diphenylmethanediisocyanate available from Huntsman

Application Example 1 Process for Preparing Spray FormulationPolyurethane Foams Using the Flame Retardant Compositions

The procedure for the foam preparation was as follows: The polyols,water, surfactant, flame retardant (abbreviated “FR” in the tablesbelow) and catalysts were weighed, placed in a mixing beaker and mixedto form a homogeneous solution. To this solution was added HFC-245fa,and after additional mixing, while maintaining its weight againstvaporization, the polymeric isocyanate was added. The mixture wasbriefly stirred at 20° C. at 5500 rpm for 3 sec and poured into acardboard cake-box. The foam thus formed was held for at least 24 h atroom temperature and then removed from the box and cut into testspecimens with a saw. The samples were then tested for flammabilityaccording to the DIN 4102 B2 test procedure (a flame height of 15.0 cmor less means that the foam has passed the test). Table 1 presents theingredients and parameters for the foam preparation and the results ofthe tests.

TABLE 1 Spray formulation system (mixed at 20° C.) Composition (g)Example 1 Terate HT5100 48 Jeffol 4 425X 25 FR of Example(F-3014/FR-513/Preparation 12 Example 1 30/30/40%) Polycat 77 1.0 DABCOBL-11 1.0 DC193 1.0 Bicate 8210 0.6 Water 2.5 HFC-245fa 6.8 Total 97.9Isocyanate, g (Urestyl-10) 104.5 MDI Index, % 101 Mix time, sec (6000rpm) 3 Rise time, sec 11 Br, P content in polyol mixture, wt % 4.92;0.73 Br, P content in foam, wt % 2.42 Foam density kg/m³ (lbs/ft³) 28.0(1.75) Flame height, cm (DIN 4102) 14.0

Application Example 2

Process for Preparing Rigid Polyisocyanurate Foams (PIR) with MDI Index300% Using the Flame Retardant Compositions

The procedure for the foam preparation was as follows:

The polyols, water, surfactant, flame retardant and catalysts wereweighed, placed in a mixing beaker, and mixed to form a homogeneoussolution. To this solution was added pentane, and after further mixing,the polymeric isocyanate. The mixture was then stirred at 20° C. at 3500rpm for 6 sec and poured into a cardboard cake-box. The foam thus formedwas held for at least 24 h at room temperature and then removed from thebeaker and cut into test specimens with a saw. The samples were thentested for flammability according to the DIN 4102 B2 test procedure (aflame height of 15.0 cm or less means that the foam has passed thetest). Table 2 summarizes the ingredients and parameters for the foampreparation and the results of the testing of the foams.

TABLE 2 PIR formulation system (mixed at 20° C.) Composition (g) Example2 Terate 2541 100 FR of Preparation Example 1 15 DMCHA 1.5 DABCO TMR301.0 Tegostab B8460 1.5 Kosmos 75 1.0 Water 1.0 Pentane 13 Total 134Isocyanate, g 250.8 MDI Index, % 300 Mix time, sec 6 Cream time, sec 11Gel time, sec 40 P content in polyol mixture, wt % 1.68 P content infoam, wt % 0.58 Foam density kg/m³ (lbs/ft³) 29.9 (1.87) Flame height,cm (DIN 4102) 13.8

Application Example 3

The application of the new compounds of the present invention isdemonstrated through their use as flame retardants in standardformulations for flexible polyurethane foams (Application Example 3). Inaddition to the flame retardant, the following components were used inthe preparation of the foams:

Materials Manufacturer Voranol 8136 Polyether Polyol Dow Desmophen 2200BPolyester Polyol Covestro Niax A-1 amine catalyst Momentive Niax C-131NPF Momentive Niax DMP Momentive Niax L-537XF Momentive Dabco 33 LVamine catalyst Air Products T-10 tin catalyst Air products B-8232silicone surfactant Evonik TDI 80 Bayer Materials TDI 65 Bayer MaterialsHydroxyl-functional phospholene-1-oxide of ICL Preparation Examples 1and 2.

Process for Preparing Flexible Polyurethane Foams

Foam samples were prepared by mixing the polyol and hydroxyl-functionalphospholene-1-oxide of Preparation Examples 1 and 2 separately. Theremaining components of the formulation, including water, aminecatalyst, silicone surfactant and tin catalyst except for theisocyanate, were added and stirred into the polyol/hydroxyl-functionalphospholene-1-oxide mixture at 2500 rpm for 30 seconds for polyetherfoam, 1000 rpm for 60 seconds for polyester foam Immediately afteraddition and incorporation of the isocyanate into the reaction mixturewith vigorous stirring, the complete reaction mixture was then pouredinto an 8×8×5″ (20×20×20 cm) box and allowed to rise fully. The box wasthen placed in a ventilated hood for 24 hours curing at roomtemperature. The top and bottom 0.5″ of the foam sample was removed, aswell as the paper lining sides of the foam. Samples were then cut andtested for flammability, including Federal Motor Vehicle Safety StandardNo. 302 (FMVSS 302), California Technical Bulletin 117 (CAL 117, 2000);volatilization per DIN 75201 Gravimetric and VDA 277. Scorch was done bymeasuring Delta E, the color differences between foam samples and acolor standard. Foam samples were placed in a 180° C. oven for 30, 60,90 and 120 minutes. Delta E was then measured at the above timeintervals. Higher value in Delta E means higher discoloration.

Tables 3 and 4 below and the above table and explanation in ApplicationExample 3 present the ingredients and parameters for the foampreparation and the results of the tests. FIGS. 1 and 2 below presentthe scorch/discoloration evaluation results of the foam.

TABLE 3 Polyether flexible foam formulation system and test resultsExample 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7Formulation (parts by weight) Polyol Voranol 8136 100    100 100 100 100100 100 Flame Retardant — Fyrol From — Fyrol From From FR-2 Prep. Ex. 1FR-2 Prep. Ex. 1 Prep. Ex. 2 FR Loading — 8.00 4.00 — 12.00 6.00 4.00Water 3.55 3.55 3.3 4.5 4.5 4.3 3.3 Niax A-1 0.06 0.06 0.06 0.06 0.060.06 0.06 Dabco 33LV 0.19 0.19 0.19 0.19 0.19 0.19 0.19 Tegostab B82320.70 0.70 0.70 0.70 0.70 0.70 0.70 Stannous Octoate T-10 0.32 0.44 0.130.34 0.41 0.09 0.13 TDI Index <110> <110> <110> <110> <110> <110> <110>Physical Properties Density (pcf) 1.80 1.80 1.80 1.50 1.60 1.50 1.80 AirFlow (scfm) 3.70 3.30 3.50 4.70 4.60 4.70 3.60 Wt % P in Foam — 0.370.41 — 0.52 0.55 0.45 Flame/Emission Test FMVSS 302 Fail SE SE Fail SESE SE/NBR CAL 117 Fail Pass Pass Fail Pass Pass N/A (Section A, 2000)Normal Conditioning CAL 117 Fail Pass Pass Fail Pass Pass N/A (SectionA, 2000) Dry Heat conditioning CAL 117 Fail Fail Pass N/A N/A N/A N/ASmoldering (Section D, 2000) Fogging DIN-75201 0.95 1.34 0.89 0.81 1.290.79 N/A Gravimetric (mg) VDA 277 Total 74.8  141.5 68.0 38.4 59.4 36.1N/A Carbon Emission (μg C/g)

TABLE 4 Polyester flexible foam formulation system and test resultsFormulation Example 8 Example 9 Example 10 Desmophen 2200B 100 100 100Flame Retardant — Fyrol A300-TB Preparation Example 1 FR Loading — 7 3Water 4.0 4.0 4.0 Niax C-131NPF 1.1 1.1 1.1 Niax DMP 0.2 0.2 0.2 NiaxL-537XF 1.3 1.3 1.3 TDI Index <98> <98> <98> (40% TD80 60% TD65)Physical Properties Density (pcf) 1.80 1.90 1.80 Air Flow (scfm) 1.101.00 0.90 wt % P in Foam — 0.33 0.30 Flame/Emission Test FMVSS 302 FailSE SE FMVSS 302 Fail SE SE Humid aged (115° C. 100% RH 3 h) FoggingDIN-75201 5.20 5.66 5.49 Gravimetric (mg)

Application Example 4

Process for preparing Low Density (0.5 lbs./ft³) spray formulationpolyurethane foams using the flame retardant compositions based onhydroxyl-functional phospholene-1-oxide of Preparation Example 8.

The procedure for the foam preparation was as follows:

The polyols, water, surfactant, flame retardant (abbreviated “FR” in thetables below) and catalysts were weighed, placed in a mixing beaker andmixed to form a homogeneous solution. To this solution the polymericisocyanate was added. The mixture was briefly stirred at roomtemperature at 5500 rpm for 3 seconds and poured into a 1 litercardboard cup. The foam thus formed was held for at least 24 hours atroom temperature and then removed from the box and cut into testspecimens with a saw. The samples were then tested for flammabilityaccording to the Oxygen Index test procedure under ASTM d. Table 5presents the ingredients and parameters for the foam preparation and theresults of the tests.

TABLE 5 Low-Density Spray formulation system Composition (g) Example 1Multranol 3901 (OH No. 28) available from Covestro 28 Jeffol SG 360 (OHNo. 360) available from Huntsman 10 Hydroxyl-functionalphospholene-1-oxide of 25 Preparation Example 8 Surfonic N-95 (OH No.88) surfactant available from 12.0 Huntsman DABCO BL-19 Amine Catalystavailable from Air 2.0 Products Tegostab B-1048 Surfactant availablefrom Evonik 2.0 Dabco T Amine Catalyst available from Air Products 4.0Water 20.0 Total 103 Isocyanate, g (Rubinate M eq. wt. 135 availablefrom 128.4 Huntsman) MDI Index, % 39 Mix time, sec (5500 rpm) 3 Risetime, sec 12 P content in polyol mixture, wt % 3.28 P content in foam,wt % 1.6-1.7 Foam density kg/m³ (lbs/ft³) 9.0 (0.56) LOI, % (ASTM D2863) 22.0

1. A rigid or semi-rigid polyurethane or polyisocyanurate comprising ahydroxyl-functional phospholene-1-oxide compound of the formula (I):

wherein: the dashed line indicates a double bond located between thecarbon atom at position 3 and one of the carbon atoms at positions 2 and4, provided that each of the two ring carbon atoms which are not part ofthe double bond are each bonded to one of the two hydrogen atoms shownin the structural formula (I-A); R¹, R², R³ and R⁴ are independentlyselected from H, a linear or branched alkyl group containing from 1 to 4carbon atoms, or chlorine; and, X is either or

(Z)_(k)—R⁷ or

and when X is Z is

(Z)_(k)—R⁷, Z is —(Y—O)_(n)—, wherein Y is a linear or branched alkylenegroup containing from 2 to 8 carbon atoms and n represents an integerfrom 1 to 20; k may be 0 or 1; R⁷ is selected from hydrogen, ahydroxy-terminated linear or branched alkylene group containing from 2to about 8 carbon atoms; and, provided that when k is zero, R⁷ is thehydroxy-terminated linear or branched alkylene group and when k is 1, R⁷is hydrogen, and when X is

 R⁵ and R⁶ are each independently selected from H, a linear or branchedalkyl group containing from 1 to 8 carbon atoms, a linear or branchedalkenyl group containing from 2 to 8 carbon atoms, a hydroxyalkyl groupcontaining from 2 to 4 carbon atoms, a halo-substituted alkyl groupcontaining from 1 to 8 carbon atoms, an alkoxy group containing from 1to 8 carbon atoms, an aryl group containing from 6 to 12 carbon atomsand an alkylaryl group containing from 7 to 16 carbon atoms, or R⁵ andR⁶ are bonded to each other to form a cycloalkyl group containing from 5to about 8 carbon atoms.
 2. The rigid or semi-rigid polyurethane orpolyisocyanurate of claim 1 wherein the hydroxyl-functionalphospholene-1-oxide compound has the formula (I-A-1):


3. The rigid or semi-rigid polyurethane or polyisocyanurate of claim 1wherein the hydroxyl-functional phospholene-1-oxide compound has theformula (I-A-2):


4. A rigid or semi-rigid polyurethane or polyisocyanurate comprising aphosphorus-containing polyol reaction product of the partialphosphorylation of a polyalcohol, which comprises at least onephosphorus-containing group, of the formula (I-B):

wherein: the dashed line indicates a double bond located between thecarbon atom at position 3 and one of the carbon atoms at positions 2 and4, provided that each of the two ring carbon atoms which are not part ofthe double bond are each bonded to one of the two hydrogen atoms shownin the structural formula (I-B); R¹, R², R³ and R⁴ are independentlyselected from H, a linear or branched alkyl group containing from 1 to 4carbon atoms, or chlorine, each of n¹ and n² is an integer equal to orgreater than 1, with n¹+n² being equal to or greater than 3, and Z² is amoiety derived from a branched polyol which has a valence of n¹+n², andis of the general formula:

wherein R is selected from the group consisting of:

and where each R⁸ independently is H or is an alkyl of from 1 to 4carbon atoms, x is ≥1, y is 2 or 3; z is an integer of from 2 to 5; and,m≥1.
 5. The rigid or semi-rigid isocyanurate of claim 1 wherein theisocyanurate is any one of a foam, a coating, an adhesive and anelastomer.
 6. The rigid or semi-rigid polyurethane or polyisocyanurateof claim 1 further comprising at least one halogenated ornon-halogenated flame retardant.
 7. The rigid or semi-rigid polyurethaneor polyisocyanurate of claim 6, wherein the halogenated flame retardantis tribromoneopentyl alcohol of formula (VII):


8. The rigid or semi-rigid polyurethane or polyisocyanurate of claim 6,wherein the halogenated flame retardant is at least onetribromophenol-terminated compound of formula (VI):

wherein n, the degree of polymerization, is an integer in the range of 0to
 5. 9. The rigid or semi-rigid polyurethane or polyisocyanurate ofclaim 6, wherein the halogenated flame retardant is a brominated flameretardant selected from the group consisting of brominated bisphenol Acompounds, brominated bisphenol S compounds, brominated bisphenol Fcompounds, brominated bisphenol A carbonate oligomers, brominatedbisphenol A epoxy resins, end-capped brominated bisphenol A epoxy resin,aliphatic brominated alcohols and glycols, dibromoneopentyl glycol,brominated phthalates and tetrabromophthalate diols, brominatedphosphates, brominated phenols, brominated phthalic acids, andcombinations thereof.
 10. An application selected from the groupconsisting of imitation lumber, insulation, packaging, footwear,gasketing, viscoelastic (“memory”) foam chemistries, air filter anddecorative facings for speakers, foam sheets produced on laminatingmachines, facings or vapor barriers, and flotation applications whichcomprises the rigid or semi-rigid polyurethane or polyisocyanurate ofclaim
 1. 11. The insulation of claim 10 which is selected from, tank andpipe insulation, applied by sheet, molding and spray techniques,insulation for refrigerators, insulation for freezers, insulation forwater heaters, panel insulation for roofs, panel insulation for walls,ceiling insulation, floor insulation, and window and door insulation.12. A roof structure comprising the panel insulation for roofs of claim11.
 13. A wall structure comprising the panel insulation for walls ofclaim
 11. 14. A rigid or semi-rigid polyurethane or polyisocyanuratefoam comprising the reaction product of a polyol, a polyisocyanate and ahydroxyl-functional phospholene-1-oxide compound of the formula (I):

wherein: the dashed line indicates a double bond located between thecarbon atom at position 3 and one of the carbon atoms at positions 2 and4, provided that each of the two ring carbon atoms which are not part ofthe double bond are each bonded to one of the two hydrogen atoms shownin the structural formula (I-A); R¹, R², R³ and R⁴ are independentlyselected from H, a linear or branched alkyl group containing from 1 to 4carbon atoms, or chlorine; and, X is either

(Z)_(k)—R⁷ or

and when X is

(Z)_(k)—R⁷, Z is —(Y—O)_(n)—, wherein Y is a linear or branched alkylenegroup containing from 2 to 8 carbon atoms and n represents an integerfrom 1 to 20; k may be 0 or 1; R⁷ is selected from hydrogen, ahydroxy-terminated linear or branched alkylene group containing from 2to about 8 carbon atoms; and, provided that when k is zero, R⁷ is thehydroxy-terminated linear or branched alkylene group and when k is 1, R⁷is hydrogen, and when X is

 R⁵ and R⁶ are each independently selected from H, a linear or branchedalkyl group containing from 1 to 8 carbon atoms, a linear or branchedalkenyl group containing from 2 to 8 carbon atoms, a hydroxyalkyl groupcontaining from 2 to 4 carbon atoms, a halo-substituted alkyl groupcontaining from 1 to 8 carbon atoms, an alkoxy group containing from 1to 8 carbon atoms, an aryl group containing from 6 to 12 carbon atomsand an alkylaryl group containing from 7 to 16 carbon atoms, or R⁵ andR⁶ are bonded to each other to form a cycloalkyl group containing from 5to about 8 carbon atoms.
 15. The rigid or semi-rigid polyurethane orpolyisocyanurate foam of claim 14 wherein the hydroxyl-functionalphospholene-1-oxide compound has the formula (I-A-1):


16. The rigid or semi-rigid polyurethane or polyisocyanurate foam ofclaim 14 wherein the hydroxyl-functional phospholene-1-oxide compoundhas the formula (I-A-2):


17. A rigid or semi-rigid polyurethane or polyisocyanurate foamcomprising the reaction product of a polyol, a polyisocyanate and aphosphorus-containing polyol reaction product of the partialphosphorylation of a polyalcohol, which comprises at least onephosphorus-containing group, of the formula (I-B):

wherein: the dashed line indicates a double bond located between thecarbon atom at position 3 and one of the carbon atoms at positions 2 and4, provided that each of the two ring carbon atoms which are not part ofthe double bond are each bonded to one of the two hydrogen atoms shownin the structural formula (I-B); R¹, R², R³ and R⁴ are independentlyselected from H, a linear or branched alkyl group containing from 1 to 4carbon atoms, or chlorine, each of n¹ and n² is an integer equal to orgreater than 1, with n¹+n² being equal to or greater than 3, and Z² is amoiety derived from a branched polyol which has a valence of n¹+n², andis of the general formula:

wherein R is selected from the group consisting of:

and where each R⁸ independently is H or is an alkyl of from 1 to 4carbon atoms, x is ≥1, y is 2 or 3; z is an integer of from 2 to 5; and,m≥1.